Most of my competition 9mm is loaded with wst. I shoot mostly 147gr but it works with any wt 9mm bullet. I prefer it to TG, but then I have never been a TG fan.
I run 3.5gr under a 147gr coated lead, about 910fps in a g19. For 124gr, 4.5gr runs about 1030fps, same g19. Both are well below max imo.

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